1. Field of the Invention
The present invention relates to a digital stereo camera/digital stereo video camera, a 3-dimensional display, a 3-dimensional projector, and a printer and a stereo viewer, and in particular to a digital stereo camera or a digital stereo video camera, a 3-dimensional display, a 3-dimensional projector, and a printer and a stereo viewer which achieve improvement in reproducibility of a 3-dimensional stereoscopic image.
2. Description of the Prior Art
There has been a long history in a 3-dimesional (3-D) stereo photograph or a 3-D stereo motion picture where a viewer or observer can view a stereoscopic image by watching two images with different viewpoints photographed at places spaced to right and left individually at his/her left and right eyes. In order to obtain a preferable stereoscopic effect in the stereo photographic, it is important to achieve positional matching between a left image and a right image. When a mismatching occurs, the stereoscopic effect is reduced or diminished, or considerable visual fatigue is given to a viewer.
In a conventional stereo camera or stereo slide of a silver halide film type, many means for taking matching at a photographing time or means for taking matching when a film is mounted on a slide mount have already been proposed by the assignee of the present application (Japanese Patent No. 2880131, Japanese Patent No. 2880132, Japanese Patent No. 3370051, and the like).
As a technique for a stereo photograph in a digital camera, for example, there is a proposal about a technique where a prism type stereo adapter having two set of left and right mirrors is attached to a photographing lens of an ordinary digital camera having one photographing lens, and a stereo photograph is taken by projecting images incident on the left and right mirror on respective left and right halves of an image-capture device in a divisional manner (Japanese Patent Application No. 2001-341789)
As a 3-D motion picture appreciating method where a viewer appreciates a 3-D stereo motion picture projected on a projection screen by a liquid crystal projector, such a method have been conventionally implemented that a linear polarizing processing where a left eye side image and a right eye side image are orthogonal to each other or a circular polarizing processing where rotating directions are reverse to each other and an image is projected on a projection screen is performed, a viewer uses glasses having linear polarizing filters or circular polarizing filters corresponding to the image on the left eye side and the right eye side to separate the image entering in both the left and right eyes into a left side eye image and a right side eye image thereby appreciating a 3-D stereoscopic image.
When a scanning type electronic display such as a CRT or a liquid crystal display is used, a 3-D cinema system where in an interlace scanning constituting one frame with two fields, a motion picture is displayed by alternately scanning a left eye side image and a right side eye image for each one field, and when a viewer watches a screen wearing liquid crystal shutter glasses with a left side liquid crystal shutter and a right side liquid crystal shutter alternately opened and closed so that a left side image appears on his/her left eye and a right side image appears on his/her right eye is known (for example, see JP-A-H10-133801).
For a stereo photograph, it is important to obtain a positional matching between a pair of left and right images (adjustment of a distance where a viewer can see a stereo-composite image). Regarding the matching, however, since there are also various factors affecting visual matching including not only positions of main subject images on left and right images but also a photographing distance to the main subject or a distance between optical axes of left and right photographing lenses, a positional relationship between the main subject image and other subject images or a background, and the like, it is difficult to obtain an optimal matching by performing a uniform adjustment.
That is, in order to produce a stereo photograph with quality higher than that of a stereo photograph to which matching adjustment has not been performed, the stereo photograph to which coarse matching adjustment has been performed, or the like, it is necessary to perform adjustment to stereoscopic feeling for each one photographing or for each production of a pair of stereo photo-prints or stereo slides. There is a similar requirement in the 3-D cinema, where matching adjustment should be performed for each one scene. However, it seems that an art about a digital stereo camera or 3-D projector provided with a matching adjusting unit or means which can attain adjustment to a complete state has not been known at this time.
Therefore, a technical problem to be solved arises in order to perform matching adjustment of left and right screens for a pair of stereo photographs or for each one scene of a 3-D cinema at a photographing time or after photographing easily and accurately. An object of the present invention is to solve the above problem.
Another object of the invention is to allow accurate matching adjustment such that a distance relationship between a stereoscopic image and “a stereo window” (one virtual window through which right and left image frames appear at a certain distance in conformity with each other) is made easily visible at a photographing time or at a time of matching adjustment between left and right screens after photographing.
A conventional digital silver halide print system used in a photo shop or the like does not accommodate a stereo photograph, and can not perform matching adjustment between left and right screens at a printing time. Still another object of the invention is to provide a printer which allows easy accurate matching adjustment between left and right screen at a printing time, allows printing of one sheet of stereo photograph on which a pair of left and right images have been arranged properly, and can provide stereo photograph print service at a photo shop or the like